1. Field of the Invention
The present invention relates to an image forming apparatus having a battery.
2. Description of the Prior Art
Although conventional copying apparatuses use an AC power source, a portable copying apparatus has recently been proposed for the purposes of miniaturization and personalization and a battery is used as a power source of this apparatus.
However, as the battery deteriorates, the voltage decreases and the apparatus cannot be driven, and it is difficult for the user to predict this occurrence. Thus, there is a drawback such that a apparatus is stopped during the copying operation or a miscopy is produced. In addition, since the amount of residual power source of the battery cannot be preliminarily detected, there is an inconvenience such that the battery cannot be exchanged with a new battery at a proper time.
On the other hand, in conventional image forming apparatuses, for example, copying apparatuses or the like, an electronic circuit of a series regulator CR as shown in FIG. 1 or a switching regulator SR as shown in FIG. 2 is used as a power supply of such an apparatus. However, it is obvious that the power supply by way of such an electronic circuit cannot be used at the location where the AC power supply cannot be obtained. In addition, the field of the apparatuses for personal use among the copying apparatuses has recently remarkably been developed and the reduction in size and weight of the copying apparatus has been gradually realized. An electrical arrangement as shown in, e.g., FIG. 3 is used as a conventional electrical arrangement of the small-sized copying apparatus. The arrangement will be practically explained hereinbelow. In FIG. 3, P denotes a power plug; NF is a noise filter; S a door switch; M a main motor; LA a halogen lamp of a light source to expose an original; Ul a lamp regulator to control a lighting voltage of the lamp LA; FM a fan motor to absorb the exhaust heat in the apparatus and ozone; H a fixing heater; Q a triode AC switch to switch a current supply to the heater H; DCP a DC power supply; Ua an AC driving element unit to control AC loads of the main motor, lamp LA, and the like; Us an operation unit through which the operator inputs a copying mode or the like; Uc a DC control unit to discriminate the input information from the operator and perform a sequence control of the copying operation; and Vdc a DC power source voltage.
However, the copying apparatus according to the conventional system as mentioned above has a problem such that it is not fitted to the copying apparatus of the battery driving type to which the present invention is embodied since electric power consumptions of the halogen heater H and halogen lamp LA are large.